Fuel tank filling alarm and method of installing it



R. A. MILNES Sept. 22, 1959 FUEL TANK FILLING ALARM AND METHOD OF INSTALLING IT Filed March 18, 1958 lNvr rroR E0362! A. Main United States Patent Robert A. Milnes, West Point, Pa., assignor to Richard E. Messmer, Radley Cross, and Robert A. Milnes, Bala Cynwyd, Pa.

Application March 18, 1958, Serial No. 722,292

3 Claims. (Cl. 116-112) My invention relates to a means of telling when a fuel tank is sufliciently full and a method of installation of such means.

A purpose of my invention is to provide such a means which shall be exceptionally easy and inexpensive to install, yet thoroughly satisfactory in use.

A further purpose is to provide such a means which can be installed in an existing fuel tank in a house or other building without even going into the building to do so.

' A further purpose is to enormously reduce the time, trouble and expense required for installing such a means, and to provide a method of installation for this purpose.

Further purposes will appear in the specification and claims.

My invention is illustrated in the drawings by an embodiment chosen from the standpoints of convenience in illustration, satisfactory operation, and clear demonstration of the principles involved.

Figure 1 is a perspective View of a fuel tank in which a filling alarm according to my invention has just been installed.

Figure 2 shows the air outlet pipe and associated structure of the fuel tank, in longitudinal fragmentary section, together with a fragmentary elevation, partly broken away, of a filling alarm according to my invention in the interior thereof.

Figure 3 is a cross section of Figure 2 along the lines 3-3.

Figure 4 is an end view of the filling alarm of Figure 2 before insertion.

Figure 5 is an elevation of the whistle which forms part of the filling alarm of Figure 2.

Figure 6 is a cross section of Figure 5 along the lines 5-5.

Figure 7 is a reduced scale fragmentary axial section similar to Figure 2 showing a modification.

In fuel tanks, such as those in the basements of homes to hold oil for use in furnaces, it is important when the fuel tank is being filled for the operator to be able to tell when the fuel tank is full or nearly so. If the truck driver does not have any way of telling this, he has a choice between two undesirable alternatives. One alternative is to leave oif filling the tank long before the tank is anywhere near full, thus necessitating much more frequent trips to fill, with the attendant greater expense, and a danger that the tank may become empty at some critical time, leaving the household without heat. The other alternative is for the truck driver to run a grave danger of filling beyond the maximum point, in which case the oil will run up the air outlet pipe and out into the yard, which not only wastes fuel but has other undesirable consequences as well. Not only is the oil messy in general, but there are likely to be fiagstones in the neighborhood of the air outlet pipe, and the oil, in spilling on the flagstones will blacken them. Indeed, such spilled oil is likely to create enough mess in this and other ways to disgust the owner of the premises after one or two occasions, and result in his going to another fuel dealer.

For these reasons, an audible alarm such as a whistle is often installed in the top of the tank in some fashion to warn the truck driver when the tank is nearly full.

Unfortunately, at the time when such a device is easiest to install, that is, at the time the tank is originally put in, the builder who would normally have the responsibility of installing the tank will often not bother to install the alarm. It is extra expense to him, on the surface it is likely to appear more to the benefit of the fuel dealer than the future owner of the house, and therefore something which the owner of the house is likely not himself to be willing to pay for, but the builder must pay out of his own pocket.

As a result, any such alarm is very often omitted at the time the house is built and must be put in, if at all, by the fuel dealer later on. This involves considerable expense, together with the trouble involved in gaining access to the interior of the house and cleaning up afterwards, and a risk that in the course of installation the top of the tank will be split, necessitating a replacement of the whole tank at the fuel dealers expense.

By use of the present invention, these difficulties can be obviated and with greatly decreased trouble and expense and actually superior result secured.

My invention in the form illustrated involves taking special ball, tube and whistle arrangement 10 and inserting it from the outside into air outlet pipe 12 of fuel tank 14 by applying suction from the outside to the outer end of fuel pipe 16.

Considering this more in particular, ball, tube and whistle arrangement ill consists of a flexible tube 18, preferably of some suitable plastic such as neoprene, to one end of which is attached ball 20 and to the other end of which is attached whistle assembly 22.

The plastic tube in the preferred form shown is round in cross-section and substantially smaller in diameter than the air outlet pipe, and preferably much smaller in diameter than itsay on the order of one third.

The tube has attached to it at the bottom end a suit ably metallic clip 24 which has an overall U-shape contour with the bottom 26 of the U extending across the opening 25 at the end of the tube and at the top of the U the clip bends in each case in through the wall of the tube at 36 and 32 respectively and is then bent back down at 34 and 36 respectively, against the inside of the wall of the tube. Thus the clip is firmly attached to both opposite walls of the tube near the end and holds the respective walls in a fixed position apart from each other.

Hanging on around the bottom of the clip is circular chain link 38, suitably of metal.

Hanging on around link 38 is head 40 of metallic pin 42, the body of which is fixedly embedded in ball 20. Ball 20 is preferably of oil resisting rubber and of a diameter just slightly less than the least inside diameter at any point of the air outlet pipe 12. Because in practice joints or elbows of such pipe are often unreamed, this may be considerably less than the inside diameter of the greater part of the length of this pipe. If desired, it may be of some other nonmetallic material, such as wood or plastic.

Whistle member 22 includes whistle 50, multifinger member 52 mounted thereon and whistle inlet tube 54, mounted on the inlet end of the whistle.

The whistle itself can take any form suitable to give an audible signal with the flow of air out through it. In the form shown in the whistle consists of bottom member 56, head 58 and intermediate wall member 60. Bottom member 56 is a short tubular member, circular in cross section, open at the lower end and closed off entirely at the top by wall member 60 except for a curved hole 62 through the wall member. Curved hole 62 is located just to the inside of the tube wall of the bottom member, and narrows in the upward direction, its inner curved wall 63 tapering outwardly in the upward direction.

Intermediate Wall member 60, in addition to extending completely across the top of bottom member 56 except for the hole, projects out beyond bottom member 56 to form eccentric circular flange 64 whose eccentricity relative to bottom member 60 is such that along one edge its edge is substantially tangent to the outside edge of the bottom member while at the opposite edge, which is that nearest to hole 62, it extends well beyond it.

Head 58 is of a more or less cylindrical shape with a slight taper in the direction of the top end and the top end is closed, and a hole 65 in the side wall is located directly above hole 62 in the flange. This form of whistle gives a quite audible sound with comparatively small passage of air.

The multifinger member surrounds the whistle just below the flange, and in the unconfined state its radiating fingers 66 stretch out and at the same time slope gradually upwardly in the same direction as the head end of the whistle. The whistle member as a whole is attached to the upper end of the tube by its inlet member being inserted into that upper end. When the whistle member is in the pipe, the fingers 66, being made of plastic as is indeed the entire radiating finger member, press throughout most of their length against the sides of the air outlet pipe, but with the inner ends 68 of the interstices between fingers being open to passage of air therethrough within the pipe. In this position, the bottom end of the flexible tube, with its ball and the elements attaching it to the ball, will be hanging down into the interior of the tank, with the tube as a whole stretched up through the air outlet pipe to a point near the outlet thereof at which the whistle and associated apparatus will be positioned.

In some cases the multifinger member is mounted directly on the flexible tube 18 at a position below the whistle rather than being mounted on the whistle or at the point where the whistle is connected to the flexible tube 18. Figure 7 illustrates the flexible tube 18 carrying a multifinger member provided with radiating fingers 66 surrounding the flexible tube 18 and secured thereon by an engagement of a hub or sleeve 66 of the multifinger member around the flexible tube 18. In this case the multifinger member is located at the upper end of the flexible tube 18 but a substantial distance below the whistle.

-To install the ball, tube and whistle arrangement of the present invention in a fuel tank setup, the following method is preferred:

After removing the cover 69, and anything else such as a screen, from air outlet pipe 12, a certain amount of oil is poured down it to lubricate it.

A tube 70 to which some pump or other source of air suction is applied, is attached by means of collar 72 to the outer end of fuel pipe 16, after having removed from the outer end of the fuel pipe any lid, cover or the like which may be on it. On the vacuum tube '70 is a suitable meter 74 to measure the vacuum therein induced.

The ball 20 of the ball and tube of my invention is then inserted in the air outlet pipe 12.

Once the ball is inside, the vacuum in the interior tends to pull the ball down the air outlet pipe, and tube 18 after it. At the same time, because of the relative difficulty of air getting in past the ball, the vacuum gage 74 will have a reading of a comparatively high amount of vacuum. When the ball reaches the inner end of the air outlet pipe at 78 and passes from it into the interior of the fuel tank, a sudden rush of air, unimpeded any longer by the presence of the ball in the outlet pipe, will come in through the air outlet pipe and the vacuum recorded by gage 74 will suddenly become much less. In practice,

in a typical installation, the gage may drop 12 inches of mercury in vacuum reading, for example, at this time. The operator will then seize the tube at the outer end, the flexible tube having been up to this point preferably in an uncut state and extending much longer than the tube as eventually used will be. He will cut off the tube at a point about two inches above the outer end of the air outlet pipe. He will then insert into this upper end of the flexible tube the whistle inlet tube of the whistle memher, and will push the whistle member in until the Whistle will be completely within the air outlet pipe, but not far below the outer end thereof. U

The device is thus installed, and any covers or the like can be put back on the air outlet pipe and fuel pipe.

Thus the ball, tube and whistle arrangement of my present invention is capable of very quick and easy installation, without the necessity of going into the house or basement at all, and with a minimum of expense.

Furthermore, once installed, it is decidedly superior to the present form of warning device. In the present form of warning device, with the whistle on a short pipe on the top of the tank inside the cellar, it is rather difficult to hear the whistle on the outside where the truck driver is putting in the fuel, and he must often bend down and apply his ear to the air outlet pipe to obviate this difiiculty. This often involves more nuisance than might be realized, because the air outlet pipe may be low and inaccessible and the ground in the vicinity will often be covered with snow or mud, the filling being mostly done in the winter and other vigorous seasons. This difficulty is' obviated in the case of the present invention, where the whistle can readily be heard without taking any such trouble.

In view of my invention and disclosure variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention without copying the combined apparatus and method shown, and I, therefore, claim all such insofar as they fall within the reasonable spirit and scope of my claims.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. A sounding device for a fuel tank having an air outlet pipe, said outlet pipe having its inner end connected to the upper portion of said tank and its outer end remote from said tank, comprising a flexible air tube, an air-actuated whistle operatively connected to one end of said air tube, vacuum-responsive means affixcd to the end of said air tube remote from said whistle and having an effective cross sectional area substantially equal to the cross-sectional area of said outlet pipe for drawing said tube and whistle from the outer end of said outlet pipe toward the inner end thereof in response to a vacuum at the inner end of said outlet pipe and retaining means cooperative between the walls of the pipe and the air tube for retaining said tube and whistle at a fixed position relative to the inner end of said outlet pipe.

2. The sounding device of claim 1 wherein the vacuum responsive means comprises a flexible ball having a diameter substantially that of the inside of said outlet pipe.

3. The sounding device of claim 2 further comprising means for connecting said ball to said air tube and holding the end of said tube adjacent said ball in an open condition.

References Cited in the file of this patent UNITED STATES PATENTS 2,140,559 Scully 1.. Dec. 20, 1938 2,522,207 Bold Sept. 12, 1950 2,681,031 McGillis June 15, 1954 2,751,877 Boone June 26, 1956 

